/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.classfile.visitor;

import proguard.classfile.Clazz;
import proguard.classfile.constant.ClassConstant;
import proguard.classfile.constant.visitor.ConstantVisitor;
import proguard.classfile.util.SimplifiedVisitor;

/**
 * This <code>ConstantVisitor</code> delegates its visits to class constants to another given
 * <code>ConstantVisitor</code>, except for classes that are extended or implemented by a given class. This exception
 * includes the class itself.
 *
 * @author Eric Lafortune
 */
public class ImplementingClassConstantFilter extends SimplifiedVisitor implements ConstantVisitor {
    private final Clazz implementingClass;
    private final ConstantVisitor constantVisitor;

    /**
     * Creates a new ImplementingClassConstantFilter.
     * 
     * @param implementingClass the class whose superclasses and interfaces will not be visited.
     * @param constantVisitor the <code>ConstantVisitor</code> to which visits will be delegated.
     */
    public ImplementingClassConstantFilter(Clazz implementingClass, ConstantVisitor constantVisitor) {
        this.implementingClass = implementingClass;
        this.constantVisitor = constantVisitor;
    }

    // Implementations for ConstantVisitor.

    public void visitClassConstant(Clazz clazz, ClassConstant classConstant) {
        Clazz referencedClass = classConstant.referencedClass;
        if (referencedClass == null || !implementingClass.extendsOrImplements(referencedClass)) {
            constantVisitor.visitClassConstant(clazz, classConstant);
        }
    }
}